Field of the Invention
The present invention relates to a wireless communication technique and, more particularly, to support of a handover process in wireless communication connection.
Description of the Related Art
In recent years, there exist many terminal devices having a wireless LAN function as typified by a smartphone and a digital camera. Japanese Patent Laid-Open No. 2010-124308 (patent literature 1) discloses a digital camera that searches for a wireless LAN access point (to be referred to as an AP hereinafter) while moving, and connects with a detected AP, and downloads data from a server. When moving through a space where a number of APs are placed, the digital camera can continue the wireless LAN communication by automatically switching the AP to be connected using the technique. The process of switching the AP to be connected will be referred to as a handover process hereinafter.
When a communication terminal searches for an AP in the neighborhood, the search process needs to be executed for a frequency (communication channel) used by the AP. Hence, when performing the search process for a frequency different from the frequency of the AP currently connected to the communication terminal, the communication terminal cannot communicate with the currently connected AP. That is, in the technique described in patent literature 1, the digital camera cannot communicate with the server while it is searching for the AP of the handover destination. As a result, the throughput may lower, or a data packet may be lost at the time of handover.